I have been playing around with electronics again.. There are a couple tutorials around on building PCB but do you guys use smd parts or through hole parts?? Also when making a PCB do you cover the traces with something or leave them open ??

I have been playing around with electronics again.. There are a couple tutorials around on building PCB but do you guys use smd parts or through hole parts?? Also when making a PCB do you cover the traces with something or leave them open ??

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Normally, I try to use SMT parts when they're not too small to handle and solder, such as 0805 caps and resistors, and chips with 0.05" spaced pins.
And after I've finished (and thoroughly tested) a circuit built on a PCB, I normally cover the traces with lacquer to protect them from corrosion as much as possible.

I've done a bit of SMT. My hands are still steady. It's the eyes that go weak first. If I can get enough light and magnification, my back is aching in 2 hours. I guess that's a job for young people.

Hang on...it's almost full daylight now. I have to go jack up a 5300 pound car when there is enough light to find the jacking points.
Just glad it has 16 inch wheels. I have to find my glasses before I can find the 14 inch wheels.

I haven't done any boardwork for a few years (miss it and hope to get back to it some time). I was doing as much SMT as I could. I have a decent MetCal set up with a decent binocular microscope which makes doing anything down to 0.5 mm pitch parts and 0402 decides pretty doable. Having to constantly flip the board over to do through hole gets annoying, plus the games you often have to play to keep the components from dropping too far out before you get them soldered is a time waster. I just find SMT to be a cleaner assembly process, even though I still do fine-pitch work one pin at a time.

In the past I have left the traces bare. I've been meaning to experiment with Krylon Clear Coat before soldering, I've been told it will get out of the way of soldering and leave the rest of the board with a conformal coat. Been meaning to do this for years, when I do I'll post the results.

I prefer through hole. I make my boards with toner transfer and sometimes leave the toner on the traces, but copper oxidation doesn't concern me.

My hands are still steady enough to do SMT, but I need a magnifying glass to inspect the joints on the tiny stuff. I made several SMT to SIP adapters yesterday for some SOT-416 devices, which are about half the size of SOT-23. I didn't feel like etching the boards, so I used a Dremel tool with a 3/32" engraving cutter. I soldered with my soldering iron because I couldn't adjust the air low enough on my hot air tool to keep the parts from moving.

I've been using three coats Krylon Clear for decades to help preserve the wiring diagrams pasted inside new air conditioners. It's almost useless in 12 years...about when you really need a diagram. Maybe that's because I'm spraying paper and moisture gets in behind the coating. Still, it's better than the three or four years the drawings last when you don't spray them at all.

I guess I'm still recommending Krylon Clear. Most consumer goods aren't even designed to need a label after 10 years, and it probably works better on top of a waterproof surface than it does on a piece of paper.